Equation of State of Uranium Dioxide: Data Collection / Edition 1

by C. Ronchi, I.L. Iosilevski, E.S. Yakub

Overview

In the beginning of the 1990’s, in the course of the events which were rapidly cha- ing the political configuration of the East European countries, the crisis which - vested the vast research apparatus of the former Soviet Union was entailing con- quences whose dimension and depth were immediately realized by the international scientific community. In the same years, however, the most important branch of nuclear energy - search and development,in particular that concerning fissionreactor,was worldwide undergoing a substantial reduction due to a variety of decisional situations. Yet, paradoxically, it was a very good fortune that a number of concerns on the future of nuclear research were shared by East- and West-European scientists, especially those who were working in advanced fields. In fact, the only hope for coping with an uncertain future was to erect bridges between similar institutions and employ safeguarding tactics linked to a long term collaboration strategy. A decade later, this proved to be a winning decision, since the revival of nuclear energy is presently starting from a basis of common intentions and a network of established cooperation, whose seeds are to be searched in those initial, individual efforts.

Product Details

ISBN-13:	9783540221227
Publisher:	Springer Berlin Heidelberg
Publication date:	08/26/2004
Edition description:	2004
Pages:	356
Product dimensions:	6.10(w) x 9.25(h) x 0.03(d)

Table of Contents

1 Introduction.- 1.1 Reactor Accident Analysis and Fuel Equation of State.- 1.2 The Role of Equation of State.- 1.3 Equation of State for Liquid UO2: Historical.- 1.4 Summary of the New Equation of State Features.- 1.5 General Notations.- 2 Governing Equations and Fundamental Formulae.- 2.1 Introduction.- 2.2 The Concept of Equation-of-State.- 2.3 Model Equations of State.- 2.3.1 Ideal Gas.- 2.3.2 Ideal Reacting Gas.- 2.3.3 Hard Bodies.- 2.3.4 Soft Spheres.- 2.3.5 Van der Waals’ Model.- 2.3.6 Lennard-Jones Fluid.- 2.3.7 Charged Spheres.- 2.3.8 Composite Models.- 2.4 Physical and Chemical Models in Thermodynamics of Reacting Fluids.- 2.4.1 The Concept of Composition.- 2.4.2 Neutral Models of UO2±x.- 2.4.3 Ionic Models.- 2.4.4 MIX Models.- 2.5 Conclusions.- 3 Ionic Models for Liquid Urania.- 3.1 Restricted Primitive Ionic Model.- 3.2 Extended Ionic Model.- 3.3 Local Equations of State for the Liquid Phase: General Requirements.- 3.4 Improved Restricted Primitive Ionic Model.- 3.5 Compatibility Conditions.- 3.6 Determination of the Coulomb Contribution.- 3.7 Conclusions.- 4 Gas-Liquid Coexistence in Uranium Dioxide.- 4.1 General Conditions of the Phase Equilibrium.- 4.1.1 Single-Component Fluids.- 4.1.2 Chemically Reactive Systems without Ionisation.- 4.1.3 Congruently Coexisting (Azeotropic) Compositions.- 4.1.4 Extremal Properties of the Thermodynamic Functions in the Azeotropic Points.- 4.1.5 Systems of Charged Species.- 4.1.6 Chemically Reacting Fluids with Ionisation.- 4.2 Calculation of the Equilibrium Composition and Thermodynamic Functions.- 4.3 General Structure of the Liquid-Vapour Phase Boundaries in UO2±x.- 4.4 Equilibrium Properties and Composition of UO2±x.- 4.4.1 Liquid Phase at Low Temperatures.- 4.4.2 Vapour Phase without Ionisation.- 4.4.3 Partially Ionised Vapour Phase.- 5 Application of the Chemical Model within the van der Waals Approximation.- 5.1 Non-Congruent Evaporation over UO2±x.- 5.1.1 Assumptions.- 5.1.2 Calibration.- 5.1.3 Results.- 5.2 Oxygen Potential.- 5.2.1 Simplified Calibration Procedure.- 5.2.2 Calibration in the Case of Non-Congruent Evaporation.- 5.3 Composition of the Liquid Phase.- 5.4 Discussion.- 5.5 Justification of the MIX Models.- 6 New Equation of State for Fluid Uranium Dioxide Based on Thermodynamic Perturbation Theory.- 6.1 Thermodynamic Perturbation Theory.- 6.1.1 Simple Fluids.- 6.1.2 One-Fluid Approximation.- 6.2 Fluids Composed of Molecules with Anisotropic Interaction.- 6.2.1 Averaged Diameter of Non-Spherical Molecules.- 6.2.2 Effective Molecular Diameter.- 6.2.3 Estimation of the Anisotropy Parameter.- 6.3 Conclusions.- 7 Thermodynamic Properties of UO2, as Predicted by the New Equation of State.- 7.1 Summary of the Model Features.- 7.2 Calibration.- 7.3 Validation of the INTAS-99-EOS.- 7.3.1 Density.- 7.3.2 Total vapour pressure.- 7.3.3 Heat capacity and thermal coefficients.- 7.4 Non-Congruent Equilibrium and Critical Point.- 7.4.1 Oxygen potential of liquid UO2.- 7.4.2 Enthalpy on the vapour-liquid boundary.- 7.4.3 Equilibrium composition and non-ideality effects.- 7.4.4 Azeotropic compositions.- 7.4.5 Critical point in FCE approximation.- 7.4.6 Critical point under non-congruent evaporation.- 7.5 Concluding Remarks.- A Appendix.- A.1.2 Volume Changes on Melting.- A.1.3 Thermal Expansion.- A.1.4 Elastic Properties and Adiabatic Compressibility.- A.1.6 Enthalpy and Entropy of Fusion.- A.1.8 The Congruently Vaporising Compositions of Urania.- A.2 Individual Components. Tables of Thermodynamic Functions.- A.3 Estimated Molecular and Ionic Interaction Constants.- A.3.1 Polarisability of Atomic O and U.- A.3.3 Dispersion Constants.- A.3.6 Conclusions.- A.4 Thermodynamic Tables.- References.